Technical Field
Embodiments of the present invention are related to teleoperated robotic surgery and, in particular, to sealing multiple surgical instruments in a single cannula.
Discussion of Related Art
Minimally invasive surgery (MIS) (e.g., endoscopy, laparoscopy, thoracoscopy, cystoscopy, and the like) allows a patient to be operated upon through small incisions by using a camera and one or more elongated surgical instruments introduced to an internal surgical site. The surgical site often comprises a body cavity, such as the patient's abdomen. The body cavity may optionally be distended using a clear fluid such as an insufflation gas, typically CO2. In traditional minimally invasive surgery, the surgeon manipulates the tissues by using hand-actuated end effectors of the elongated surgical instruments while viewing the surgical site on a video monitor.
One or more cannulas may be passed through small (generally 7 cm or less) incisions or a natural body orifice to provide entry ports for the minimally invasive (e.g., endoscopic, laparoscopic, and the like) surgical instruments, including a camera instrument (e.g., endoscope, laparoscope, and the like). A surgeon is able to perform surgery by manipulating the surgical instruments from outside the body while viewing the instrument end effectors at the internal surgical site with images provided by the camera instrument.
It is typical to provide several cannulas for a minimally invasive surgical procedure. Generally, each cannula will provide access to the surgical site for a single surgical or camera instrument. For example, four cannulas may be provided with one cannula being used to introduce a camera instrument and the remaining three cannulas being used to introduce surgical instruments. The use of two or more separate entry points to access a surgical site may be considered “multi-port” minimally invasive surgery. While the small incisions necessary for placing a cannula are less traumatic than the incision necessary for open surgery, each incision still represents a trauma to the patient.
In an effort to reduce the trauma of minimally invasive surgery even further, techniques are being developed to allow minimally invasive surgery using only a single access port into the body, such as a single incision or single natural body orifice. This access may be accomplished by using a somewhat larger cannula that can accommodate all of the instruments required for the surgery. Minimally invasive surgery performed through a single incision or natural orifice may be referred to as single port access (SPA) surgery. The single cannula that provides the single port may be introduced through a body orifice or through an incision.
If multiple surgical instruments and/or camera instruments are to be introduced to a surgical site through a single cannula, it can become difficult to manage the instruments within the cannula. It is desirable to use as small a cannula as possible, consistent with the size of the instruments to be passed through the cannula. This may make it difficult to introduce the necessary instruments and to maintain the necessary mobility of the instruments as well as to prevent the insufflation gas from escaping via the access port as various instruments are inserted and removed from the cannula, as well as during instrument use during surgery.
Therefore, there is a need to develop systems for better and more effective access to the surgical area.